1. Field of the Invention
The present invention relates generally to a transmission lubrication arrangement and, more particularly, to an arrangement that promotes efficient lubrication of mechanical elements such as bearings and gears which are disposed on rotational shafts for power transmission.
2. Description of the Related Art
In the prior art, the lubrication of a transmission, especially for supplying lubrication oil to bearings, gears, etc., which are provided around rotational shafts for power transmission, is realized by providing axially extending passages in the respective rotational shafts and by providing radially extending passages to lead lubrication oil from these axially extending passages to the outer surfaces of the respective shafts. in this arrangement, lubrication oil discharged from a hydraulic pump is supplied to oil passages which are connected to the respective axially extending passages. in some cases, these passages are provided additionally with partition walls which include orifices to control the flow of lubrication oil (for example, refer to Japanese Patent Publication No. H7 (1995)-68894 (B). lubricate bearings, gears, etc., which are disposed on the shafts, by the force produced from the discharge pressure of the hydraulic pump and by the centrifugal force generated from the rotation of the shafts.
However, this type of arrangement or method is not very effective for supplying a sufficient amount of lubrication oil to the bearings, gears, etc., disposed on the input shaft and the output shaft which are arranged with one end of one of these shafts facing one end of the other shaft. The reason is hat, because of this structural arrangement, the flow of lubrication oil through the passage which is located between these two shafts tends to be disrupted. A front engine rear wheel drive transmission (FR drive transmission) is an example of a transmission which has such a structural arrangement.